According to Heron's formula,the area of a triangle $=$ ...........

Find the area of a triangle whose sides are $33 \, cm$,$34 \, cm$,and $65 \, cm$. (in $, cm^2$)

The area of an equilateral triangle is equal to ............

$A$ field is in the shape of a trapezium whose parallel sides are $25\, m$ and $10\, m$. The non-parallel sides are $14\, m$ and $13\, m$. Find the area of the field. (in $, m^{2}$)

The triangular side walls of a flyover have been used for advertisements. The sides of the walls are $122\, m, 22\, m$ and $120\, m$ (see Fig.). The advertisements yield an earning of $Rs. 5000$ per $m^2$ per year. $A$ company hired one of its walls for $3$ months. How much rent did it pay?

In parallelogram $ABCD$,$AB = 9 \, cm$,$BC = 10 \, cm$ and $AC = 17 \, cm$,then find its area. (in $, cm^2$)